The recognition of the prosodic focus position in German-learning infants from 4 to 14 months

The aim of the present study was to elucidate in a study with 4-, 6-, 8-, and 14-month-old German-learning children, when and how they may acquire the regularities which underlie Focus-to-Stress Alignment (FSA) in the target language, that is, how prosody is associated with specific communicative functions. Our findings suggest, that 14-month-olds have already found out that German allows for variable focus positions, after having gone through a development which goes from a predominantly prosodically driven processing of the input to a processing where prosody interacts more and more with the growing lexical and syntactic knowledge of the child

The Processing of Accented Speech

This thesis examines the processing of accented speech in both infants and adults. Accents provide a natural and reasonably consistent form of inter-speaker variation in the speech signal, but it is not yet clear exactly what processes are used to normalise this form of variation, or when and how those processes develop. Two adult studies use ERP data to examine differences between the online processing of regional- and foreign-accented speech as compared to a baseline consisting of the listeners’ home accent. These studies demonstrate that the two types of accents recruit normalisation processes which are qualitatively, and not just quantitatively, different. This provided support for the hypothesis that foreign and regional accents require different mechanisms to normalise accent-based variation (Adank et al., 2009, Floccia et al., 2009), rather than for the hypothesis that different types of accents are normalised according to their perceptual distance from the listener’s own accent (Clarke & Garrett, 2004). They also provide support for the Abstract entry approach to lexical storage of variant forms, which suggests that variant forms undergo a process of prelexical normalisation, allowing access to a canonical lexical entry (Pallier et al., 2001), rather than for the Exemplar-based approach, which suggests that variant word-forms are individually represented in the lexicon (Johnson, 1997). Two further studies examined how infants segment words from continuous speech when presented with accented speakers. The first of these includes a set of behavioural experiments, which highlight some methodological issues in the existing literature and offer some potential explanations for conflicting evidence about the age at which infants are able to segment speech. The second uses ERP data to investigate segmentation within and across accents, and provides neurophysiological evidence that 11-month-olds are able to distinguish newly-segmented words at the auditory level even within a foreign accent, or across accents, but that they are more able to treat new word-forms as word-like in a familiar accent than a foreign accent

Temporal Variability and Stability in Infant-Directed Sung Speech: Evidence for Language-specific Patterns.

In this paper, sung speech is used as a methodological tool to explore temporal variability in the timing of word-internal consonants and vowels. It is hypothesized that temporal variability/stability becomes clearer under the varying rhythmical conditions induced by song. This is explored crosslinguistically in German – a language that exhibits a potential vocalic quantity distinction – and the non-quantity languages French and Russian. Songs by non-professional singers, i.e. parents that sang to their infants aged 2 to 13 months in a non-laboratory setting, were recorded and analyzed. Vowel and consonant durations at syllable contacts of trochaic word types with ¦CVCV or ¦CVːCV structure were measured under varying rhythmical conditions. Evidence is provided that in German non-professional singing, the two syllable structures can be differentiated by two distinct temporal variability patterns: vocalic variability (and consonantal stability) was found to be dominant in ¦CVːCV structures whereas consonantal variability (and vocalic stability) was characteristic for ¦CVCV structures. In French and Russian, however, only vocalic variability seemed to apply. Additionally, findings suggest that the different temporal patterns found in German were also supported by the stability pattern at the tonal level. These results point to subtle (supra) segmental timing mechanisms in sung speech that affect temporal targets according to the specific prosodic nature of the language in question

Prosodic boundary phenomena

Synopsis: In spoken language comprehension, the hearer is faced with a more or less continuous stream of auditory information. Prosodic cues, such as pitch movement, pre-boundary lengthening, and pauses, incrementally help to organize the incoming stream of information into prosodic phrases, which often coincide with syntactic units. Prosody is hence central to spoken language comprehension and some models assume that the speaker produces prosody in a consistent and hierarchical fashion. While there is manifold empirical evidence that prosodic boundary cues are reliably and robustly produced and effectively guide spoken sentence comprehension across different populations and languages, the underlying mechanisms and the nature of the prosody-syntax interface still have not been identified sufficiently. This is also reflected in the fact that most models on sentence processing completely lack prosodic information. This edited book volume is grounded in a workshop that was held in 2021 at the annual conference of the Deutsche Gesellschaft für Sprachwissenschaft (DGfS). The five chapters cover selected topics on the production and comprehension of prosodic cues in various populations and languages, all focusing in particular on processing of prosody at structurally relevant prosodic boundaries. Specifically, the book comprises cross-linguistic evidence as well as evidence from non-native listeners, infants, adults, and elderly speakers, highlighting the important role of prosody in both language production and comprehension

Infants segment words from songs - an EEG study

Children’s songs are omnipresent and highly attractive stimuli in infants’ input. Previous work suggests that infants process linguistic–phonetic information from simplified sung melodies. The present study investigated whether infants learn words from ecologically valid children’s songs. Testing 40 Dutch-learning 10-month-olds in a familiarization-then-test electroencephalography (EEG) paradigm, this study asked whether infants can segment repeated target words embedded in songs during familiarization and subsequently recognize those words in continuous speech in the test phase. To replicate previous speech work and compare segmentation across modalities, infants participated in both song and speech sessions. Results showed a positive event-related potential (ERP) familiarity effect to the final compared to the first target occurrences during both song and speech familiarization. No evidence was found for word recognition in the test phase following either song or speech. Comparisons across the stimuli of the present and a comparable previous study suggested that acoustic prominence and speech rate may have contributed to the polarity of the ERP familiarity effect and its absence in the test phase. Overall, the present study provides evidence that 10-month-old infants can segment words embedded in songs, and it raises questions about the acoustic and other factors that enable or hinder infant word segmentation from songs and speech

Parents’ hyper-pitch and low vowel category variability in infant-directed speech are associated with 18-month-old toddlers’ expressive vocabulary

The present study examines the acoustic properties of infant-directed speech (IDS) as compared to adult-directed speech (ADS) in Norwegian parents of 18-month-old toddlers, and whether these properties relate to toddlers’ expressive vocabulary size. Twenty-one parent-toddler dyads from Tromsø, Northern Norway participated in the study. Parents (16 mothers, 5 fathers), speaking a Northern Norwegian dialect, were recorded in the lab reading a storybook to their toddler (IDS register), and to an experimenter (ADS register). The storybook was designed for the purpose of the study, ensuring identical linguistic contexts across speakers and registers, and multiple representations of each of the nine Norwegian long vowels. We examined both traditionally reported measures of IDS: pitch, pitch range, vowel duration and vowel space expansion, but also novel measures: vowel category variability and vowel category distinctiveness. Our results showed that Norwegian IDS, as compared to ADS, had similar characteristics as in previously reported languages: higher pitch, wider pitch range, longer vowel duration, and expanded vowel space area; in addition, it had more variable vowel categories. Further, parents’ hyper-pitch, that is, the within-parent increase in pitch in IDS as compared to ADS, and lower vowel category variability in IDS itself, were related to toddlers' vocabulary. Our results point towards potentially facilitating roles of increase in parents’ pitch when talking to their toddlers and of consistency in vowel production in early word learning

Children\u27s Sensitivity to Pitch Variation in Language

Children acquire consonant and vowel categories by 12 months, but take much longer to learn to interpret perceptible variation. This dissertation considers children’s interpretation of pitch variation. Pitch operates, often simultaneously, at different levels of linguistic structure. English-learning children must disregard pitch at the lexical level—since English is not a tone language—while still attending to pitch for its other functions. Chapters 1 and 5 outline the learning problem and suggest ways children might solve it. Chapter 2 demonstrates that 2.5-year-olds know pitch cannot differentiate words in English. Chapter 3 finds that not until age 4–5 do children correctly interpret pitch cues to emotions. Chapter 4 demonstrates some sensitivity between 2.5 and 5 years to the pitch cue to lexical stress, but continuing difficulties at the older ages. These findings suggest a late trajectory for interpretation of prosodic variation; throughout, I propose explanations for this protracted time-course

From Acoustic Segmentation to Language Processing: Evidence from Optical Imaging

During language acquisition in infancy and when learning a foreign language, the segmentation of the auditory stream into words and phrases is a complex process. Intuitively, learners use “anchors” to segment the acoustic speech stream into meaningful units like words and phrases. Regularities on a segmental (e.g., phonological) or suprasegmental (e.g., prosodic) level can provide such anchors. Regarding the neuronal processing of these two kinds of linguistic cues a left-hemispheric dominance for segmental and a right-hemispheric bias for suprasegmental information has been reported in adults. Though lateralization is common in a number of higher cognitive functions, its prominence in language may also be a key to understanding the rapid emergence of the language network in infants and the ease at which we master our language in adulthood. One question here is whether the hemispheric lateralization is driven by linguistic input per se or whether non-linguistic, especially acoustic factors, “guide” the lateralization process. Methodologically, functional magnetic resonance imaging provides unsurpassed anatomical detail for such an enquiry. However, instrumental noise, experimental constraints and interference with EEG assessment limit its applicability, pointedly in infants and also when investigating the link between auditory and linguistic processing. Optical methods have the potential to fill this gap. Here we review a number of recent studies using optical imaging to investigate hemispheric differences during segmentation and basic auditory feature analysis in language development

How tone, intonation and emotion shape the development of infants' fundamental frequency perception

Fundamental frequency (ƒ0), perceived as pitch, is the first and arguably most salient auditory component humans are exposed to since the beginning of life. It carries multiple linguistic (e.g., word meaning) and paralinguistic (e.g., speakers’ emotion) functions in speech and communication. The mappings between these functions and ƒ0 features vary within a language and differ cross-linguistically. For instance, a rising pitch can be perceived as a question in English but a lexical tone in Mandarin. Such variations mean that infants must learn the specific mappings based on their respective linguistic and social environments. To date, canonical theoretical frameworks and most empirical studies do not view or consider the multi-functionality of ƒ0, but typically focus on individual functions. More importantly, despite the eventual mastery of ƒ0 in communication, it is unclear how infants learn to decompose and recognize these overlapping functions carried by ƒ0. In this paper, we review the symbioses and synergies of the lexical, intonational, and emotional functions that can be carried by ƒ0 and are being acquired throughout infancy. On the basis of our review, we put forward the Learnability Hypothesis that infants decompose and acquire multiple ƒ0 functions through native/environmental experiences. Under this hypothesis, we propose representative cases such as the synergy scenario, where infants use visual cues to disambiguate and decompose the different ƒ0 functions. Further, viable ways to test the scenarios derived from this hypothesis are suggested across auditory and visual modalities. Discovering how infants learn to master the diverse functions carried by ƒ0 can increase our understanding of linguistic systems, auditory processing and communication functions